Related papers: The crucial problem: the electroweak symmetry brea…
Without going to the details, I give a short, qualitative and historical description of the development of the Standard Model, from quantum electrodynamics, further through quantum chromodynamics, then to weak interactions with parity- and…
The LHC data have confirmed the Standard Model as the correct theory at the electroweak scale. It successfully explains the experimental results with high precision and all its ingredients, including the Higgs boson, have been finally…
1. Introduction 2. Status of the Data 3. Precision Electroweak Data and the Standard Model 4. A More General Analysis of Electroweak Data 4.1 Basic Definitions and Results 4.2 Experimental Determination of the Epsilon Variables 4.3…
Electroweak baryogenesis is severely challenged in its traditional settings: the Minimal Supersymmetric Standard Model, and in more general two Higgs doublet models. Fine tuning of parameters is required, or large couplings leading to a…
Supersymmetric extensions of the Standard Model have been in vogue for over half a century. They have many interesting theoretical properties like calculability, absence of quadratic divergences, and phenomenologically impactful features…
The status of precision electroweak data, tests of the standard model, determination of its parameters, and constraints on new physics, are surveyed.
We study the possibility of radiative electroweak symmetry breaking where loop corrections to the mass parameter of the Higgs boson trigger the symmetry breaking in various extensions of the Standard Model (SM). Although the mechanism fails…
We propose a new class of four-dimensional theories for natural electroweak symmetry breaking, relying neither on supersymmetry nor on strong dynamics at the TeV scale. The new TeV physics is perturbative, and radiative corrections to the…
In 5 dimensions the electroweak symmetry can be broken by boundary conditions, leading to a new type of Higgsless theories. These could in principle improve on the 4D case by extending the perturbative domain to energies higher than $4 \pi…
A number of observed phenomena in high energy physics and cosmology lack their resolution within the Standard Model of particle physics. These puzzles include neutrino oscillations, baryon asymmetry of the universe and existence of dark…
We review the theoretical underpinning of the Higgs mechanism of electroweak symmetry breaking and the experimental status of Higgs measurements from a pedagogical perspective. The possibilities and motivations for new physics in the…
We argue that a Standard Model decoupling limit is generically the necessary ingredient which makes scenarios of electro-weak symmetry breaking viable. This applies especially also to models of dynamical electro-weak symmetry breaking.…
We discuss some cosmological implications of extensions of the Standard Model with hidden sector scalars coupled to the Higgs boson. We put special emphasis on the conformal case, in which the electroweak symmetry is broken radiatively with…
We introduce the standard model of elementary particles and discuss the reasons why we have to modify it. Emphasis is put on the indications from the neutrinos and on the role of the Higgs particle; some promising theoretical ideas, like…
The Standard Model may be included within a supersymmetric theory, postulating new sparticles that differ by half-a-unit of spin from their standard model partners, and by a new quantum number called R-parity. The lightest one, usually a…
Recently, a new class of realistic models for electroweak symmetry breaking have been constructed, without supersymmetry. These theories have naturally light Higgs bosons and perturbative new physics at the TeV scale. We describe these…
The Principle of Naturalness of small parameters of a theory is reviewed. While quantum field theories constructed from gauge fields and fermions only are natural, those containing elementary scalar fields are not. In particular the Higgs…
Experiments have confirmed the presence of a mass gap between the Standard Model and potential New Physics. Consequently, the exploration of effective field theories to detect signals indicative of Physics Beyond the Standard Model is of…
We present a new solution to the electroweak hierarchy problem. We introduce $N$ copies of the Standard Model with varying values of the Higgs mass parameter. This generically yields a sector whose weak scale is parametrically removed from…
A heavy fourth generation with a mass of the order of 400 GeV or more could trigger dynamical electroweak symmetry breaking by forming condensates through the exchange of a fundamental Higgs scalar doublet. The dynamics leading to these…